Spring-clamp for stereoscopes.



No. 766,698. PATBNTED AUG. 2, 1904.

. T. W. INGERSOLL.

SPRING CLAMP FOR STEREOSCOPES.

APPLICATION FILED MAR.10, 1904.

N0 MODEL.

WITNESSES, INYENTUR,

/m (.4 0 760 m 1 21) THUMB-1N WARE INEEE'SULL.

BY HIS ETTURNEY,

UNITED STATES PATENT OFFICE.

TRUMAN WVARD IN GERSOLL, OF ST. PAUL, MINNESOTA, ASSIGNOR TO H. C. \VHITE (10., OF NORTH BENNINGTON, VERMONT, A CORPORATION OF VERMONT.

SPRING-CLAMP FOR STEREOSCOPES.

SPECIFICATION forming part of Letters Patent No. 766,698, ated August 2, 1904.

Application filed March 10, 1904. Serial No. 197,515. (No model.)

T0 at rah/01m it may concern:

Be it known that I, TRUMAN IVARD INGER- sOLL,a citizen of the United States of America, residing at the city of St. Paul, in the State of Minnesota, have invented certain Improvements in Spring-Clamps for Stereoscopes, of which the following description, in connection with the accompanying drawings, constitutes a specification.

This invention relates to means for holding the view-holder of the common hand-stereoscope in its adjusted position on the shaft while carrying a stereograph. It has for its object to provide means whereby the viewholder may be quickly released from its binding connection with the shaft and moved along thereon without making abrasive contact therewith and after adjustment may be instantly set and firmly held in its adjusted position.

The invention is fully disclosed in the drawings, wherein Figure 1 shows the under side of a common hand-stereoscope with my improved clamp in working position. Fig. 2 shows a side elevation of the same stereoscope and a partial vertical longitudinal section thereof, taken on the line 1 2 3 of Fig. 1. Fig. 3 exhibits a similar section showing in section the loose condition of the clamp as when opened to move the view-holder along on the shaft. Fig. 4 is a section of a modification of the clamp with the fulcrum indentations omitted.

The drawings show a common stereoscope, havinga shaftA and a cross-bar B, commonly known as a view-holder, adapted to bestride and slide along the shaft. To the holder B my spring-clamp O is attached by pins or screws D D. The under side of bar B is recessed to take in the shaft a little deeper than the thickness of the shaft. The clamp is struck up from a piece of sheet metal of proper spring temper and consists of a long narrow leaf 1, from the middle of which the two wings J J project. These wings furnish the means for attachment of the spring-clamp to the bar B by the screws D D, as before stated, and the spring-plate spans the gap in the bar B through which the shaft passes.

Patented August 2, 1904.

The extremities of the leaf I are folded or 5 bent back upon themselves at the terminal folds H H toward each other, and their opposing ends are bent downwardly, as at F, to furnish finger-pads by means of which the spring-jaws may be operated. The springplate is bent to a concave form, as shown at I in Fig. 4, so that the bearing ends H H of the spring will bear against the under side of the shaft, as seen in Fig. 2. The reflected ends E E of the leaves of the spring-plate may be bent to the form shown in Fig. 4c or may have a slightly-raised boss G G struck up or attached to the inside of the reflex leaf, as seen in Fig. 3. The purpose of these features is to supply a bearing to contact with the under side of the leaf I to act as a fulcrum for the reflex leaf to oscillate upon when the springs are pressed together.

The shape of the spring should be such that when in position the ends of the leaves will bear with the proper degree of pressure to hold the part to which it is attached firmly in its relation to the other part. It is preferable that the degree of stiffness of the reflex leaf should be greater than that of the main leaf, so that the main leaf-spring in use shall yield to the movement of the reflex leaf.

The embodiment of this spring as here illustrated is only the preferred form for the uses specified. Its details and applications may be modified in various ways without departing from the principle of the invention.

IVhen this spring is applied to the viewholder of a scope in the manner shown in Fig. 1 and the same is slipped over the shaft, the ends H H of the spring will bear with sufficient pressure against the under side of the shaft to hold the two members firmly in position, so that the holder will not slide off or have any tendency to work out of position or focus by any slight disturbance. By pinching the two finger-pads F together the two fulcrum-points G Gr will be pressed against the under side of the upper leaf-springs, as seen in Fig. 3, and by reason of the reflex leaf being a little stiffer than the main leaf as the pads are brought closer together the ends H H are drawn away from contact with the shaft, so that it can-slide freely through the slot or groove in the holder, which may be slid along the shaft without scratching the same by abrasion. This feature is especially desirable in aluminium or other metallic scopes and in highly-finished Wood scopes.

I therefore claim as my invention, and desire to secure by Letters Patent, the following:

1. A clamp-spring made of a single piece of spring material having two attaching-wings projecting laterally from its middle portion, and two opposing springleaves extending from said middle portion each of which is folded back on itself toconstitute a reflex leaf, and means connected with said reflex leaves for springing them together, substantially as specified.

2'. The described clamp-spring havinglateral attaching-wings and reflex leaves each of the latter being provided with a finger-pad, substantially as specified.

3. The described clamp-spring having lateral attaching-wings andreflex leaf-springs posed between each pair of main and reflex leaves a protuberance to act as a fulcrum, substantially as specified.

5. The combination with a stereoscope and its view-holder of the described spring-clamp having means for attaching it to the holder, overfolded leaf-springs and means for operating said springs with the'thumb and finger, substantially as specified.

In testimony whereof I have hereunto subscribed my name, at the city of St. Paul, Minnesota, in the presence of two witnesses.

TRUMAN WARD INGERSOLL.

. Witnesses:

A. R. MOORE, JOHN MAILER. 

